US 11,376,476 B2Granted

Golf ball

AssigneeSumitomo Rubber Industries, Ltd.

InventorsChiemi Mikura, Kazuyoshi Shiga, Hikaru Nagakura, Ryota Sakamine

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Abstract

An object of the present invention is to provide a golf ball having an excellent flight performance on driver shots. The present invention provides a golf ball comprising a spherical core and at least one cover covering the spherical core, wherein a hardness difference D1 (H75−H0) between a hardness H75 at a point radially located at a distance of 75% from a center of the spherical core and a center hardness H0 of the spherical core is 10 or more and 27 or less in Shore C hardness, and a hardness difference D2 (Hs−H75) between a surface hardness Hs of the spherical core and the hardness H75 at the point radially located at the distance of 75% from the center of the spherical core is 0 or more and 6.5 or less in Shore C hardness.

Claims21

Dependent claims

A golf ball comprising a spherical core and at least one cover covering the spherical core, wherein

a hardness difference D1 (H75−H0) between a hardness H75 at a point located at a distance of 75% of a radius from a center of the spherical core and a center hardness H0 of the spherical core is 10 or more and 27 or less in Shore C hardness,
a hardness difference D2 (Hs−H75) between a surface hardness Hs of the spherical core and the hardness H75 at the point located at the distance of 75% of the radius from the center of the spherical core is 0 or more and 6.5 or less in Shore C hardness,
a hardness difference D5 (H75−H50) between the hardness H75 at the point located at the distance of 75% of the radius from the center of the spherical core and a hardness H50 at a point located at a distance of 50% of the radius from the center of the spherical core is 8 or more in Shore C hardness, and
a hardness difference D4 (H50−H25) between the hardness H50 at the point located at the distance of 50% of the radius from the center of the spherical core and a hardness H25 at a point located at a distance of 25% of the radius from the center of the spherical core is −3 or more and 2 or less in Shore C hardness.

1 more element

A golf ball comprising a spherical core and at least one cover covering the spherical core, wherein

a hardness difference D1 (H75−H0) between a hardness H75 at a point located at a distance of 75% of a radius from a center of the spherical core and a center hardness H0 of the spherical core is 10 or more and 27 or less in Shore C hardness,
a hardness difference D2 (Hs<H75) between a surface hardness Hs of the spherical core and the hardness H75 at the point located at the distance of 75% of the radius from the center of the spherical core is 0 or more and 6.5 or less in Shore C hardness,
a hardness difference D5 (H75−H50) between the hardness H75 at the point located at the distance of 75% of the radius from the center of the spherical core and a hardness H50 at a point located at a distance of 50% of the radius from the center of the spherical core is 6 or more 8 or more in Shore C hardness,
a hardness difference D4 (H50−H25) between the hardness H50 at the point located at the distance of 50% of the radius from the center of the spherical core and a hardness H25 at a point located at a distance of 25% of the radius from the center of the spherical core is −3 or more and 2 or less in Shore C hardness, and
the spherical core is formed from a rubber composition consisting of:
(a) a base rubber,
(b) an α,β-unsaturated carboxylic acid having 3 to 8 carbon atoms and/or a metal salt thereof as a co-crosslinking agent,
(c) at least one crosslinking initiator selected from the group consisting of dicumyl peroxide, 1,1-bis(t-butylperoxy)-3,3,5-trimethylcyclohexane, 2,5-dimethyl-2,5-di(t-butylperoxy)hexane, and di-t-butylperoxide,
(d) an unsaturated fatty acid and/or a metal salt thereof excluding an α,62 -unsaturated carboxylic acid having 3 to 8 carbon atoms and/or a metal salt thereof, and optionally at least one component selected from the group consisting of
(e) a saturated fatty acid and/or a metal salt thereof;
(f) at least one metal compound selected from the group consisting of a metal hydroxide, a metal oxide and a metal carbonate;
(g) an organic sulfur compound;
a pigment;
a filler;
an antioxidant;
a peptizing agent;
and
a softening agent.

15 more elements

Dependencies are inferred from the claim text.